Apparatuses are used for example, but in no way exclusively, for aligning printed sheets along at least one edge, with sufficient accuracy, one above the other, with the result that the stack can then be trimmed at the edges. In the case of a fair number of printed products, for example notes of value provided with registration numbers, it is necessary, once the sheets have been printed, to maintain the sequence of the sheets in the stack-forming group.
DE 68 09 156 U describes an arrangement for producing an ordered stack of flat items of mail. In this case, irregularly arriving items of mail are imbricated and set down on a stack.
German patent 12 32 986 discloses a stacking apparatus for groups of folded sheets. In this case, the imbricated groups of sheets are guided around a cylinder, and turned, by means of a belt-transporting system. The groups of sheets are then aligned against stops and stacked.
EP 0 173 959 A1 discloses a sheet-processing machine to which sheets are sent from an underside of a first stack. Following processing, the non-imbricated sheets are transported to a set-down location by means of a belt system and, by means of a suction conveyor, are set down on the top of a second stack.
EP 06 14 840 A1 discloses an apparatus which is designed in the manner of a vibrating table. A supporting table is provided for this vibrating table, lateral stops being arranged on at least two, adjacent sides of the supporting table and it being possible for these stops to come into abutment against the side edges of the sheets. In order to align the group of sheets arranged one above the other, the group is set down on the supporting table and the latter is then inclined in the direction of the two stops to the extent where the side edges of the sheets come into abutment against the stops on account of gravitational force. The vibrating table is then made to vibrate in order thus to loosen the group of sheets and to allow an aligning movement of the individual sheets relative to one another.